1. Field of the Invention
The present invention relates to a driving method, and more particularly, to a driving method for plasma displays.
2. Description of Related Art
With the development of multi-media, displays serving as an interface between human and computers are becoming more and more essential. The panel displays include plasma displays, organic electro-luminescent displays (OELD) and liquid crystal displays (LCD). With advantages like big size, self-illuminance, wide-view angle, thinness and full colors, plasma displays are promising and are gradually becoming the mainstream of the next generation of displays.
FIG. 1 is a schematic view of a conventional plasma display. Referring to FIG. 1, the conventional display panel 100 includes a front substrate 110, a rear substrate 120, scan electrodes 112, sustain electrodes 114, address electrodes 122 and ribs 30. The scan electrodes 112 and the sustain electrodes 114 are disposed in pairs on the front substrate 10. The scan electrodes 112 and the sustain electrodes 114 are covered by a dielectric layer 116 and a passivation layer 118. The address electrodes 122 and the ribs 130 are disposed on the rear substrate 120. Multiple discharge spaces 140 filled with discharge air are provided among the ribs 130, the front substrate 10 and the rear substrate 120. A fluorescent layer 150 is positioned in the discharge spaces 140 and on the rear substrate 120. The scan electrodes 112 and the sustain electrodes 114 cross the address electrodes 122 at the discharge spaces 140. When voltages are applied to the scan electrodes 112, the sustain electrodes 114 and the address electrodes 122, the discharge air discharges to produce ultraviolet light to illuminate on the fluorescent layer 150 for lighting a plasma display 100.
FIG. 2 is a timing diagram of driving signals of a conventional plasma display. The frame displayed on the plasma display is composed of multiple sub-frames. Each sub-frame includes a reset period Tr, an address period Ta and a sustain period Ts. In the reset period Tr, reset pulses 202 are applied to the scan electrodes and the sustain electrodes for reducing the residual wall charges during the last sub-frame display. Each display unit of the plasma display can be thereby kept at a same initiation state and the display of the plasma display can have an enhanced uniformity. In the address period Ta, wall charges are accumulated on the to-be-lighting display unit by applying an address pulse 204 to the address electrodes and applying a scan pulse 206 to the scan electrodes. In the sustain period Ts, the display units having wall charges discharge and light with alternate application of sustain pulses to the scan electrodes and the sustain electrodes.
In the above description, the residual wall charges in each sub-frame are removed/reduced by the reset pulses. However, when the display units are kept in the sustain period, the interruption of power will retain wall charges in the display units. When the plasma display restarts, subsequent scan pulses and sustain pulses will be input without the complete reset pulses due to the incompleteness of the driving signals initially input. If the wall charges exist, during the restarting of the plasma display, the gap voltage, which is the sum of the voltage of the wall charges and the voltage of the scan pulse or the sustain pulse, will be larger than the firing voltage of the discharge air, and this condition will make the display units to erroneously discharge with strong light.